BadMagicNumber

I was reading Joseph Pranevich's “What's new in Linux 2.6 and I noticed
this:

Another major change in the 2.6 release, is that the kernel's internal threading
infrastructure has been rewritten to allow the Native POSIX Thread Library (NPTL) to run on top of it.
This can be a major performance boost for Pentium Pro and better processors in heavily threaded applications,
and many of the top players in the “enterprise” space have been clamoring for it. (In fact, RedHat has
already backported the support to Linux 2.4 and includes it starting with RedHat 9 and Advanced Server 3.0)

I got a bit excited about this, because the dirty little secret of the “Linux/Java anti-Microsoft kabal” is that Java
on Linux usually isn't comparable to Java on Windows on the same hardware (note, I said usually!). A little searching
came up with Red Hat Linux 9 and Java 2 Platform,
Standard Edition 1.4.2: A Winning Combination, which mentions:

On a 2 X 1.6 Ghz P4 Xeon system, time to completion was 191% faster with J2SE 1.4.2 running on NPTL,
compared with J2SE 1.41 running on the original Linux threads.

Is anyone familiar enough with this to comment as to how real this improvement is? I'd love to see someone run
ECPerf on Windows/Java 1.4.1, Windows/Java 1.4.2, Linux/Java 1.4.1 and Linux/Java 1.4.2 on identical hardware and
see how it comes out. Any takers?

Somewhat ironically a day before my previous post,
Dare Obasanjo replied to
a blog complaining about MS
Architects posting about technologies that aren't ready for production yet.. The irony that I still can't talk about JDK1.5,
despite its release date being next year is – if not Shakespearian – at least more than Morissettian.

(Those of you not interested in the hostory of various websites may want to leave now)
Incidentally, “Back in the day” I was pretty active on K5, and I remember when Dare joined (which, despite
his low uid was quite a long time after I joined – my id was in the 200's and his is over 1800). I thought he
was just another punk hacker who thought he was too cool for /. until he started posting a few stories. They always
impressed me, and I had pretty high standards. He posted some when he interviewed at Microsoft, and he thought he
was going to be working on Data Access stuff, which I found pretty interesting. Unfortunatly he went and did that XML crap instead, so
I stopped reading his stuff for a while… ;-)

Sun made the JDK1.5 Alpha available today through JavaLobby. I think that was a great move on their part, but I do think
having to click through a big disclaimer promising not to talk about it was a bad move. I'm sure Sun was worried about
people complaining about bugs or bad performance or something, but we all understand this is an alpha release, right?

Alphas always have bugs and performance problems, and those things are easily solvable. Much more important is the marketing of this,
the most significant release of Java since 1.2. There is an enormous set of wonderful features coming in Java 1.5, and here I am enjoying
them all, and dying to proclaim that Java 1.5 is the one true development environment, and it kicks the .NET's butt. Unfortunalty, I can't tell you that,
or anything else about it really – and this is for a product that is probably only 6 months from release!

Meanwhile, our friends at Microsoft have thousands of people writing about Longhorn, Avalon, WinFS etc, etc – all of which
won't be released until 2006 at the earliest. That is Sun's problem, and I hope they realise it.

It was a nice Christmas present, though – even if I won't get to play with it for a few days.

I received a nice card from Google today. I know their motto is “Don't be evil”, but I never knew a company
could be so damn nice.

Classifier4J is my Bayesian classification tool written in Java.

I have just released version 0.5, which is the first release since July (yes I'm slack).

This release has a number of new features, and perhaps most impressively actually reduces the
dependancies compared to version 0.4. Now there is one less excuse not to use it!

Watching my referers, I suspect someon of doing some fairly deep analysis of the spidering and indexing patterns of
various search engines. How else could you explain referers like http://search.msn.com/results.aspx?ps=ba%3d(0.15)0(.)0…….%26co%3d(0.15)4(0.1)3.200.2.5.10.1.3.%26isURL%3d1%26aq%3dwww%2bbug%2bgoogle%26pn%3d1%26rd%3d0%26&q=www.bug.google&ck_sc=1&ck_af=0
and http://search.msn.com/results.aspx?q=w.w.w.google.ro.&FORM=SMCRB.

I don't have any real idea what these people are hoping to achieve. I'd speculate they are testing the popularity of
various words so they can possibly game systems like adwords, or maybe to register domain names for popular word combinations.

Anyhow, it's very weird, and I'm interested in any further informed speculation.

I've uploaded the slides I did for an AOP talk I did at AJUG-Adelaide a month ago. They don't
go into a lot of depth, but hopefully they gave a good introduction.

The slides can be found here (BTW, if you are
using IE, turn on page transitions – Tools->Internet Options->Advanced Tab->Check “Enable page transitions for the full powerpoint-like effect…).

If you are having trouble similar to the issues described in KB305217,
the symptoms of which are:

When Internet Explorer version 5.5 Service Pack 1 or later tries to POST data,
GET data or set up an HTTPS connection with the connect command,
Internet Explorer generates an error message that indicates that the page could not be displayed.
This problem does not occur in Internet Explorer 5.5.

then you might find that turning off keep-alive on your webserver may fix the problem. It helped for one of our clients.
Some further info can be found in
this newsthread.

Yes, this is a fairly serious bug. No, Microsoft are not distributing a fix.

I think it would be very useful to have a Java interface to the
Java Virtual Machine Profiler Interface (JVMPI).
I suppose the performance requirements make this difficult. I believe there is some support for profiling and performance
monitoring coming in JDK1.5 – yet another thing I'd like sooner rather than later!

If (by some chance) you should need to connect a .NET client to a Java Serverside application, don't believe the
hype about webservices being slow. TEST you application – the results might surprise you. In our specific example
we tested 3 commercial .NET <-> Java communication tools, as well as Axis as the
webservice implementation. One of the three products performed better than webservices in terms of total speed and
scalability – and the pricing of that made it easy to throw clusters of webservice service machines in order to
match that performance. I'm not ashamed to admit that result surprised me somewhat!

The lesson: when concerned about performance, TEST, don't rely on your intuition.

Updated: for some reason it seems I lost this entry soon after posting it. I'm not sure why that was.